The proposed research aims to develop an improved methodology for personalized prescription hearing-aid fitting using objective, evoked measures of correlates of loudness including auditory brainstem response and otoacoustic emissions. Such a method would be particularly useful for rapidly and accurately assessing loudness growth in populations that are incapable of participating in psychoacoustical experiments, such as infants and cognitively impaired persons. It would provide a new strategy for best accounting for individual differences in loudness growth for hearing- impaired listeners with the same audiograms without extensive laboratory testing. The inclusion of a rapid, objective test of loudness in a clinical battery would allow for better personalized prescription fits to loudness growth over simply using algorithms based on audiograms. Presently, individual differences in loudness growth functions are widely ignored clinically. Typical fitting procedures assume similar loudness growth for all impaired listeners with the same degree of hearing loss. Additionally, the data obtained will provide a better understanding of the peripheral cochlear system in normal and hearing-impaired listeners. Specifically, loudness estimates will be made in listeners with normal hearing and hearing impairment using advanced signal processing techniques to analyze auditory brainstem responses and tone-burst otoacoustic emissions. These loudness estimates will be compared with more direct measures of loudness obtained using cross-modality matching and loudness comfort judgments. PUBLIC HEALTH RELEVANCE: The proposed research aims to develop an improved methodology for personalized prescription hearing-aid fitting using objective, evoked measures of correlates of loudness including auditory brainstem response and otoacoustic emissions.